Purity, Foreign Matter & Adulteration

In short

Purity covers everything that should not be in the cargo — foreign matter, other-grain admixture, hulls, soil, packaging debris and deliberate adulterants — and is verified by physical inspection plus targeted analysis.

Measured as: % foreign matter and admixture by physical separation; microscopy; NIR or DNA/species identification where authenticity is at stake

Economic adulteration follows price

Adulteration concentrates in high-value ingredients: marine proteins, amino acids, vitamins and premix components. When a market tightens, non-protein nitrogen, mineral fillers and substituted species become the risk to design for.

Microscopy is still the most cost-effective screen

Feed microscopy identifies hulls, shells, soil, urea crystals, foreign seeds and unexpected animal material quickly and cheaply, and it is admissible evidence in most claim processes. It complements, rather than competes with, instrumental methods.

What to verify

—Foreign matter and admixture limits in the contract
—Microscopy on the retained sample for high-value ingredients
—Species identification where regulatory species bans apply
—Acid-insoluble ash as a soil and sand indicator

Typical risks

—Regulatory non-compliance on prohibited materials
—Nutrient dilution
—Equipment damage from stones and metal

Common mistakes

—Relying on visual inspection of a single bag
—Skipping retained samples, which removes any basis for a later claim

Frequently asked questions

How do buyers detect economic adulteration?

By combining an unexpected analytical pattern — protein that does not match amino acids, ash that does not match calcium — with microscopy and, where warranted, targeted instrumental confirmation on a properly retained sample.